1. Technical Field
The present disclosure generally relates to media delivery systems, and more particularly, to delivering media to a home communication terminal.
2. Description of the Related Art
The cable version of Switched Digital Video (SDV) is designed to operate over existing Hybrid Fiber/Coax infrastructures to enable delivery of switched video services on the existing installed base of set tops, also referred to herein as home communication terminals (HCTs). Such HCTs can, for example, decode Moving Pictures Expert Group (MPEG) media streams.
The HCTs are in communication with a cable head end system. A cable head end system implements an SDV by allocating a number of logical channels to a number of physical channels that are provided by quadrature amplitude modulation (QAM) modulators. Each of the physical channels can, for example, correspond to a different radio frequency that carries the logical channels. This radio frequency is used by a tuner in an HCT in order to tune to, and receive, the logical channels carried on the physical channel. The logical channels can, for example, carry media content (or media programming) such as broadcast media streams (i.e. video, audio, text, etc.) or video on demand (VoD), among other types of media streams. In many cable networks, media content is transmitted on the logical channels using MPEG (e.g., MPEG-2, MPEG-4, etc.) audio/video compression. The number of logical channels carried on a physical channel is dependent upon the amount of bandwidth allocated to the channel and the allocated bitrate of each logical channel.
Once various content has been allocated by the cable head end system this allocation information is transmitted to the HCTs to provide a mapping of each of the logical channels to the physical channels. Accordingly, when the HCT is instructed to decode a particular logical channel, the HCT consults this mapping to determine which physical channel the requested logical channel is being carried upon. The HCT can then tune to the physical channel and filter the particular logical channel by, for example, its unique program identifier (PID), thereby extracting the desired content from other content received on any other logical channels.
Because physical channels are limited by the total amount of bandwidth provided by a cable operator, the cable head end typically only allocates logical channels to a particular physical channel if the logical channel is in use, or is likely to be used soon, by a particular HCT. In the event that a requested logical channel is not currently being provided on a particular physical channel, the HCT can request that the particular logical channel be provided. In such an instance, the cable head end can allocate the logical channel to a selected physical channel and notify the HCT which physical channel and logical channel the media content is being provided on. The HCT can then tune to the physical channel and receive the desired media content.
Such an SDV set up is particularly advantageous in providing a large variety of potential media content to users without the need for broadcasting every single physical channel to every HCT at the same time. That is, even though a particular cable system may only be able to physically provide 30% of the total available content to a particular neighborhood, it is common for only a small subset of available logical channels to be used by the HCTs in a particular service group at any one time. Thus a Multiple System Operator is able to provide a wide variety of content choices for their subscribers without the need for broadcasting every channel simultaneously.
Although the amount of simultaneously offered media content is on the rise, it is becoming more and more difficult to actually view this content. For example, in conventional systems, a user is not able to access more than one logical channel at a time without providing an equal number of tuners and associated infrastructure in the HCT in order to receive the content. Thus, even though an HCT may include picture-in-picture capabilities, this feature cannot be used to simultaneously view content without multiple tuners. Likewise, even though an HCT may include digital video recorder (DVR) functionality, the HCT cannot record more than a single content instance at a time or view a different content instance from the content instance being recorded without multiple tuners.
Therefore, what is needed are systems and methods that can potentially address one or more of the aforementioned deficiencies, among others.